


Xorcism

by AMegaSadNerd



Category: Undertale (Video Game)
Genre: Demon possession, Exorcism, Gen, Look two people die so be aware of that as well djsjjc, This is like... Kinda dark so uh heads up for that???, exorcist AU
Language: English
Status: Completed
Published: 2020-09-19
Updated: 2020-09-19
Packaged: 2021-03-08 04:53:45
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 1
Words: 2,345
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26550046
Author URL: https://archiveofourown.org/users/AMegaSadNerd/pseuds/AMegaSadNerd
Summary: A priest tries his best to exorcise a demon out of a close friend, only for it to backfire horribly.
Relationships: Implied Dream/Cross
Comments: 4
Kudos: 21





	Xorcism

There was a long silence in the room, the tension thick enough to cut with a knife. The dark corners of the room seemed to turn darker, and the ceiling towered over higher. Everything was quiet, save for the heavy breaths of the boy and the priest. There was not a creak, not a whistle of the wind, not even the sound of a car passing by. It's like the world had frozen for this moment, waiting to see what happened next. The priest was quiet; the boy was quiet. All the while they unconsciously relaxed, letting their guard down. Did it work? Was the demon gone? "It's gone." The priest breathed in relief, letting his tense posture melt away.

The boy was so overwhelmed that all he could do was let out a mix of a laugh and a sob. He was just about to utter the word, "Finally!" but the sudden sound of something snapping, falling, closing - whatever it was - along with a loud inhale from the priest. The boy looked over so quickly his neck could've snapped at the act. He wishes he had.

"Hello, Dream." The voice of the demon spoke through the priest. Two bright, crimson eyes glared down at the boy - Dream - with a rage like no other. But despite the unfiltered hate his eyes seemed to give off, he held an enormous smile on his face. Admittedly, it bordered on a sneer rather than a smile, but Dream's thoughts were running too fast to think of the proper word. The cross the priest was holding was now upside down and the book he held open before was shut tightly in his hand. The boy swears he could faintly hear the squeaking of the leather cover against the priest's bones.

"My, it's been ages, has it not?" The demon continued to speak, putting his arms behind his back and sauntered to the side of the bed Dream was closer to. "I had dreamt of this day many times and in many ways..." The demon made eye contact with Dream. "It's such a shame we had to meet again through such unconventional means." ... Wait.

"Brother..?" Dream uttered with horror, eye sockets blown wide. No, that's impossible. He couldn't be back. He shouldn't be back! They had all worked so hard, they had spent so many sleepless nights making sure he _wouldn't come back._ Was it all for nothing..? Nightmare laughed, his voice and the priest's intertwining and sending chills down Dream's spine. "Still clever as always, little brother. Clever little dreamboat... Too clever for his own good." 

No. "That's why they chose you, right?" No no no. "That's why you betrayed me, _is it not?_ " Dream's breath hitched, but he didn't dare speak. He'd only make the situation worse. But even then, his silence seemed to annoy his brother. "What's the matter, Dream? Cat got your tongue?" Nightmare laughed. Tears were burning at the corners of Dream's sockets. He wanted to stop them from falling, he really did, but the entire situation had him at a complete loss. Nightmare's grin turned thin and dangerous. He leaned down and put a hand on his brother's cheek. 

"Or... Did I get your tongue?~" Nightmare drawled out, his face leaning closer to his brother's. The quiet whimpers and sniffling sounded like music to Nightmare's ears after so long. A low chuckle rumbled from the priest's non-existent throat, but Dream knows by now that the priest is long gone. Now, it's only the brother he'd try to rid the world of years ago. It seems karma is a bitch after all. 

Nightmare scoffed and let his hands slowly drift down to Dream's neck. "I did, didn't I? You're absolutely speechless!" This was a bad dream. This had to be a bad dream. The priest is okay. His brother is still gone. It's a bad dream. _Just a bad dream._ Nightmare leaned closer, his sickening grin too close to Dream's face for him to be comfortable. "God, that face..." Nightmare whispered, using his hand to turn Dream's head from side to side. The poor boy couldn't help it when more tears began to stream down his face. 

Nightmare laughed and finally let go, steeping a few inches away from the bed in which Dream was still stuck to. Slowly, he finally brought the cross back int his hand. When had he stopped holding it? Dream was probably too shaken to have ever noticed. "Why don't we..." Nightmare raised the cross up high. The world seemed to stop, everything went quiet and everything went blurry. Except for the being he was looking at. His brother in the priest's body was as clear as day, every little detail seeming to stand out. Dream's eyes widened. 

"Keep it like that..." Nightmare's hand came down quickly and ruthlessly. " _Forever_." He spoke just barely above a whisper, but Dream could hear it as clear as day. The short end of the cross was stabbed through the priest's clothes and into his ribs. The sudden cracking was startling enough on its own, but then Nightmare began to twist it. He dug it deeper and deeper, the creaking and groaning of the bones making Dream sick. Marrow started to leak onto the priest's shirt - wait, no. Skeleton's marrow can't be that color. Why was it so dark..?

Dream let out a choked sob, unable to tear his eyes away from the scene no matter how much we wanted to. "No!" Dream feebly cried out, tugging at his restraints. With a sudden jolt, he found that one of the restraints had broken. Without a second thought, Dream scrambled off the bed and was fully ready to run for his life, but his other arm was still tied down tight. No no no! He was close, he had to get away!! 

Nightmare's laugh sounded again, bringing nothing but dread. Oh, how that laugh used to make him the happiest monster in the world. He felt Nightmare drawing closer, just out of sight now. "Oh, trying to leave already? Without a single word to me, your dear beloved brother? Pathetic, that's what you are, Dream." Dream hiccuped and flung his head to look at Nightmare, his headpiece falling off his head from the sheer force and speed. 

"I'm sorry, okay?! I'm sorry I couldn't save you!" Dream yelled with all his might, bones and soul aching. He's sorry, he is, but he was the one who gave them the idea. He couldn't admit to that... Unless he already knew... Is that why he's come back? Dream almost descended into a panic when he heard Nightmare laugh again. But this time, it wasn't smug or taunting. It was manic, filled with anger and sorrow and hate. Dream watched with horror as Nightmare's wounds began to spill more of the black substance. This wasn't even close to the brother he used to have. Is Hell really that cruel?

"Save us?!" Nightmare practically screamed his entire cool posture and act he had before melted. He looked like a mad man, like the true demon he was. His eye lights were waving, the black substance leaking from his eyes now. He was smiling though, fangs bared when he wasn't talking. Wait, the priest had fangs? "Don't make me laugh." Nightmare chuckled, leaning down to pick up Dream's headpiece. He ran his fingers over it slowly, staring at his reflection in the carefully cared for metal. It was a gift from him, in fact. Nightmare would admit, he was surprised Dream kept it and even seemed to take great care of it. It almost made him stop what he planned to do. Almost. 

Dream whimpered and Nightmare met his small, scared eyelights once again. "You never truly tried to save me." Dream seemed to deflate at those words, his shoulders going limp, his arms falling to his side and the tears fell faster. At this point, he could've flooded the planet with his tears. This wasn't a bad dream. This was real. Nightmare knew. Dream slowly sank to his knees, moving his gaze to stare at the floor. He couldn't look his brother in the face. Not anymore. "You thought that you could get away with sending my soul to a different world? Seriously? For someone who always got better grades and was always complimented for being the smartest of the bunch, that was a horrendously stupid move on your part." Nightmare rambled on, spinning the headpiece on one of his fingers. 

He had best get this over with quickly before someone gets suspicious. Carefully, Nightmare stalked up to Dream, crouching down in front of him. "You could have stopped them." Dream nodded weakly. "But you didn't." Dream nodded again. What was the point of hiding it if he already knew, anyway? Nightmare scoffed. "You're more than just pathetic. You're a sad, pitiful, miserable waste of life." Nightmare said each word slowly, making sure Dream heard and understood him. Dream trembles, a weak sob escaping his mouth. Nightmare had said all of those things to make his brother feel bad, but now that he was seeing him like this? He realized how true those words actually were.

He almost felt bad.

**Almost.**

As Nightmare stared down at his brother, the liquid hate began to flow faster. Through the wound, through his eyes and mouth, even dripping from his joints at this rate. If he wasn't careful it could get on Dream's headpiece. The headpiece... Nightmare grinned and put a finger under Dream's chin and forced their eyes to meet. "Tell me, brother. What do you think Hell is like?" Nightmare hummed, thriving off the look of terror his question brought Dream. But he didn't get a response. Nightmare's smile faltered and twisted into a sneer. He leaned closer to Dream. "Tell me, Dream"

Dream gulped, sensing his inevitable fate would come sooner if he didn't answer right now. "I-I... I don't know, b-brother..." Dream offered weakly. Nightmare gave an amused hum. "You don't know? Then that'll make your trip more fun." Dream was so tired of crying at this point, but he couldn't help the fresh batch of tears than fell down his cheeks and fell on his lap. Nightmare wiped a few tears away with his thumb and reached down for the headpiece. "I'll be seeing you again someday, you know that? And we'll be stuck together for the rest of our lives~" Nightmare practically sang. Dream hated it. "So, for the inevitable day that we do cross paths in the depths of Hell again..." Nightmare delicately placed Dream's headpiece on his skull, tracing the rim and letting his hands fall down his brother's face.

"Make sure to keep that on. So when the other demons see you, they'll know who you're going to spend the rest of your eternity with." Nightmare smiled and slowly took the cross out of his chest. More of the sludge began to drip out of the wound once the cross was removed and the top of it was coated as well. Even better, Nightmare thought. "Goodbye, brother. See you in hell~" Swiftly and silently, Nightmare pressed the cross into Dream's soul. Hearing the crack and the pain-stricken face of his brother that he's wanted dead for years. His screams of pain and agony were like music to Nightmare's ears, the cracking of his bones and the shattered of his soul finally bringing the older brother a sense of peace. How long had he wished for this day to come? For his brother to finally be weak enough to surrender his life like this?

Much too long, Nightmare idly thought, his eyes drifting to Dream's fingers. He was dusting. At last. "Brother..." Dream spoke. How dare he? How dare he speak to him, this isn't how this was supposed to go, he was supposed to be quiet! "I'm sorry... Okay?" His arms and legs were dust. He was almost gone. "I... I still think... You can be better than this..!" Dream coughed, dust blowing out of his mouth. Just a little more. "I... I love you, brother..." The deafening shattering sound of Dream's soul sounded, and nothing but his clothes were left.

"... Tch." Nightmare scoffed and stood up, brushing himself off. His bones ached and his head spun, but he had He looked at the door, then himself, and looked down at his wounds... 

"The demon took the boy, I'm sorry, he's gone now." Cross said solemnly, keeping his eyes glued to the floor. He couldn't bare to look Dream's mother in the eyes. Not with how... _guilty_ he was. He had lost someone... very, very close to him, after all. A quiet sob could be heard from Nim, a sound that was much too familiar. "No, you're not serious, are you?" Nim croaked out, her hand covering her mouth. Cross shook his head. "I wish I were telling a cruel joke, Ms. Joku. I really do." What he was doing was a cruel joke in itself.

Tears streamed down Nim's face, long shimmering hair falling in front of her face. Hair that he and Dream used to braid as children. "I'm sorry for your lost, ma'am. I'll leave you to grieve on your own." He didn't get a response. Good. Turning away from his mother, Nightmare couldn't help but grin as he walked out of that damned house. The house he and Dream grew up in, that he and Dream would play in, the house Dream was in when he plotted against his own fucking brother.

As he opened the front door and the sunlight fell onto his bones, he felt strangely relieved. Relieved, content, happy, and admittedly a little smug. Nightmare looked down at the priest's body. There was no doubt that the bastard was already long dead, probably worrying about his beloved in Heaven or some bullshit like that. The thought made Nightmare chuckle. He walked down the steps, his shoes hitting the pavement with a slight click.

Let's see how long he can keep up the act of being Cross.

**Author's Note:**

> uwu


End file.
